how can i input the button continuously?

The story is here:
I’m making an adventure game
In the first part of the character’s battle, I wrote the code that when pressing the “E” key, it will launch battle 1.
But when it comes to battle 2, I decided that if I press the E key again within a short amount of time from the first press, the 2nd ability will be activated.
But unfortunately, I am not qualified to do it, does anyone know how to do it?

Try it with this system:

using UnityEngine;

public class Test : MonoBehaviour
{
    public float TimeOffset = 0.15f;

    bool SecondInputInTime;

    float TimeStamp;

    void Update()
    {
        if (Input.GetKeyDown(KeyCode.E))
        {
            if (TimeStamp == 0f)
            {
                TimeStamp = Time.time;

                SecondInputInTime = false;
            }
            else
            {
                SecondInputInTime = true;
            }
        }

        if (TimeStamp > 0f && Time.time - TimeStamp > TimeOffset)
        {
            if (!SecondInputInTime)
            {
                print("Attack1");

                TimeStamp = 0f;
            }
            else
            {
                print("Attack2");

                TimeStamp = 0f;
            }
        }
    }
}

using System.Collections;
using System.Collections.Generic;
using UnityEngine;

public class combat : MonoBehaviour
{
[SerializeField] private Animator animator;

public Transform attackPoint;
public LayerMask enemyLayers;

public float attackRange = 0.5f;
public int attackDamage = 40;

public float attackRate = 2f;// giới hạn số lần tấn công trong 1 giây;
float nextAttackTime = 0f;
float nextAttack1Time = 0f;

// Update is called once per frame
void Update()
{
    if (Time.time >= nextAttackTime)
    {
        if (Input.GetKeyDown(KeyCode.E))
        {
            Attack();
            nextAttackTime = Time.time + 0.8f / attackRate;
            Debug.Log(nextAttackTime);
           
            
        }
       
    }
    if((nextAttackTime - Time.time)>=-0.5f)
    {
        if (Input.GetKeyDown(KeyCode.E))
        {
            Attack1();

        }
    }

}

void Attack()
{
    // bắt đầu hoạt ảnh tấn công.
    animator.SetTrigger("Attack");

    // phát hiện kẻ thù trong vùng tấn công.

    Collider2D[] hitEnemies = Physics2D.OverlapCircleAll(attackPoint.position, attackRange, enemyLayers);

    // tiêu diệt kẻ thù
    foreach(Collider2D enemy in hitEnemies)
    {
        //Debug.Log("We hit" = enemy.name);

        enemy.GetComponent<Enemy>().TakeDamage(attackDamage);
    }
}



void Attack1()
{
    // bắt đầu hoạt ảnh tấn công.
    animator.SetTrigger("Attack1");
    
    // phát hiện kẻ thù trong vùng tấn công.
    
    Collider2D[] hitEnemies = Physics2D.OverlapCircleAll(attackPoint.position, attackRange, enemyLayers);
    
    // tiêu diệt kẻ thù
    foreach (Collider2D enemy in hitEnemies)
    {
        //Debug.Log("We hit" = enemy.name);  ----> qua dò lỗi từng cái thì có vẻ như lỗi là từ dòng code này

        //enemy.GetComponent<Enemy>().TakeDamage(attackDamage);
    }
    
}

void OnDrawGizmosSelected()
{
    if (attackPoint == null)
        return;
    Gizmos.DrawWireSphere(attackPoint.position, attackRange);
}

}